I was feeling pretty smug about my big, nerdy vocabulary when I tried out the word challenge at Vocabulary.com, but it didn't take long for the game to find my weak spots. That's because it quickly adapts to your level and learns to predict what words you don't know. There's also an app version you can take around with you, which is good, because while there are lots of ways to kill time on your phone while waiting in line, this one actually pays off in words learned. In the past few days I've gained osculate, litotes, and flagitious.

You can customize by choosing particular word lists to work on, and while many of the lists are organized around sober, practical topics — SAT prep, current events, historical documents, great books — there are a number of lists that are just plain word fun. Here are 11 of the best themed lists from Vocabulary.com for you to master, or just enjoy.

At first it's not clear what these words have to do with pirates. Arbitrary? Artichoke? Then you realize they are words pirates might like to say. Focus on that first syllable. Draw it out a little. Draw it out a little more — now you're ready for Talk Like a Pirate Day!